I don't know how you blew up one of these things . . . Must have run low on oil at one point.
anyway, back to the thread...
You'll have a good amount wrapped up in one to make it go fast, but what you want is a 12 valve with the P-7100 injection pump. They look like a little mini 6 cyl engine hanging off the side, (kind of)
You'll be hard pressed to find one cheap though. Maybe in need of a rebuild. Usually a rebuild will only need pistons and bearings . . . maybe a re-bore depending on how hot the person got it/hot many miles are on it.
. . . Just start reading.